Replication Data for: Electrically Tunable Topological Notch Filter for THz Integrated Photonics

Electromagnetic filtering is essential for emerging integrated photonic technologies and widely adaptable processing of high-bandwidth signals. Conventional electro-optic modulator-based photonic approach for signal filtering at microwave frequencies could not be implemented at terahertz (THz) frequencies due to the unavailability of the THz signal-driven optical modulator. Here, we demonstrate an electrically tunable on-chip THz photonic notch filter based on the topologically protected valley hall waveguide-cavity platform. Our device shows a significantly large notch suppression depth of more than 20 dB with a return loss of 13 dB at in the entire tuning range of notch frequency. The feedback control circuit enabled precise control of the notch frequency shift with a minimum step size of 7 MHz. Our work extends the application of topological photonic crystals in developing THz integrated photonic devices for transformative technologies, including sixth generation (6G) communication and high-resolution spectral sensing.